City officials, neighbours, and humane society workers say they worried for years about the condition of animals housed inside a central Kitchener home, but no one realized just how serious the problem was until now.

Yesterday, the Kitchener-Waterloo Humane Society revealed that it had rescued more than 4,000 mice, 50 guinea pigs and rabbits, three turtles and two pigeons from a house at 20 Maurice St., near Charles and Ottawa streets on Wednesday.

"This is not at all what we expected," said humane society spokesperson Elizabeth Bonkink.

"We expected that some of the animals had gotten out of hand in terms of their care, but we didn't expect this volume."

Mayor Carl Zehr called the number of animals seized from the home "distressing."

The 60-year-old female homeowner was arrested by police under the Mental Health Act on Wednesday and is being held in hospital for 72 hours for a psychological assessment.

The Kitchener fire department condemned the house after finding live electrical wires had been gnawed by rodents. Fire prevention officers also had concerns about smoke detectors in the home.

The homeowner won't be allowed back into the house until the problems are rectified, Kitchener deputy fire chief Tim Beckett said.

The humane society was struggling to cope yesterday with the thousands of animals now at their Riverbend Drive facility.

The shelter had cages stacked upon cages, and aquariums filled with mice in rooms that usually house a handful of small animals.

"This is a huge problem for us," Bonkink said. "We are simply out of room to house these animals."

About 30 staff members and volunteers have been working frantically since Wednesday, trying to keep the animals fed and watered and cleaning the cages.

Despite the number of animals, Bonkink said they appeared to be well-fed and watered. "They were clearly all pets," she said.

Neighbours say they complained for nearly a decade about the house, sending letters to the public health department, humane society, bylaw officers and Zehr. But said nothing was done until Wednesday's seizure.

The city's director of bylaw enforcement, Shayne Turner, said bylaw officers had repeatedly visited the home during the past three summers and tried in vain to get the owner to let them inside. Provincial legislation doesn't allow inspectors to enter someone's home without consent.

"We had growing concerns with the condition of the inside of the property, but she would never let us in," Turner said. "The conditions just kept deteriorating and finally we said we've go to do more than just knock on her door and ask for permission."

"We have to abide by the laws. Even if it's just an animal in a car, we can't just go in and break the window," Bonkink said

Turner said bylaw officers were able to enforce some property standards on the exterior of the home, such as requiring the owner to clean up garbage and trim overgrown brush.

When the woman didn't do the cleanup herself, the city sent workers to do the job.

Inspectors frequently knocked on the woman's door, but she either didn't answer the door, or would talk to bylaw officers, but refuse to let them inside.

They turned to police about a month ago, Turner said.

"We finally got to the point where we said this has being going on long enough, we need to look at different ways of doing this because she's just not going to comply with our request to get in."

Bylaw officers often run into roadblocks trying to get inside private property, but Turner said the Maurice Street home is "one of the worst situations that Kitchener has seen in some time."

The region's public health department sent two inspectors to the house in the first week of September after getting a letter from neighbours, said Curt Monk, manager of health protection.

The inspectors couldn't get inside the home without a warrant proving there was a risk to public health, so they did a site assessment of the outside.

They couldn't find any evidence of a rodent infestation, such as huge amounts of rodent droppings, or grease marks along the fences, Monk said.

Inspectors visited the house Wednesday and determined there were no public health risks.

The city is a member of an umbrella association for municipal law enforcement, which is working to lobby the province for stronger laws.

"This isn't just a City of Kitchener problem, this is a provincial problem," Turner said.

Yesterday, a veterinarian started examinations to ensure each animal was healthy.

The shelter normally houses just eight small animals and didn't have enough food and supplies for the thousands recovered.

"We're supposed to have 12 mice to a 10-gallon aquarium," Bonkink said. "With what we have now, we're going to need 110 more aquariums to house them all."

The shelter must hold the animals until the owner signs a release or the investigation ends. Until then, none of them can be adopted out. But the humane society was asking residents to adopt other animals to make room.

The shelter is accessing an emergency grant to get supplies from a local pet store, but is appealing to the public for cash donations.